The primary aim of this proposal is to determine the amino acid sequence of aortic elastin and to relate such information to the structure of the elastin precursor, tropoelastin and ultimately to the fibrogeneses of a functioning elastic fiber. Specifically we hope to 1) establish a "normal" elastin structure from a functioning elastin tissue, 2) characterize the crosslinked areas of insoluble elastin in order to gain insight into the particular sites of tropoelastin destined for crosslink formation, 3) examine elastin from both diseased and aged tissue for such parameters as quantity and location of crosslinks, and omissions or substitutions of primary sequences and 4) investigate and locate the binding sites of lipids, lipoproteins and glycoproteins, and Ca ions in elastin preparations from normal aged and/or diseased specimens. Ultimately our goal is to understand the role of elastin in arteriosclerosis and aging with a positive contribution to prevention.